Device for the local annealing of pressed parts



DEVICE FOR THE LOCAL ANNEALING OF PRESSED PARTS Filed May 10 1924 1 r I Q WHHIIII" 5. ZZZ/Md Sawfly:

Pasha! June 15, 1926.

UNITED STATES mm scnnbnmn, or manna. Grimm-Q,

nnvrcnroa mm LOCAL ANNEAIJNG or ran-seen Pam's.

Application filed Kay 10, 1924, Serial No. 712,412, and in June 4 1921.

My invention relates to a device by which pressed parts can be annealed locally, and the gist of the invention resides therein that the zone to bev heated is switched on to the low-tension circuit of a low-tension transformer. in such a manner that the current passes only through the zone to be annealed and this zone is'heated to the desired temperature by a high load on its sectional area.

The invention is illustrated by way of example in the accompanying drawing in which Figure 1 is adiagrammatic'al view partly in vertical section (left hand part of the figure) and partlyin side-view (right hand part of the figure), of one form of the improved device;-Figure 2 is .a diagrammatical view of a modification, and Figures 3,4 and 5 show another modification, Fig. 3 being a plan of a pressed, iron potand of some electrodes contacting with it, Fig. 4.- being a vertical section through this pot, together with a side-view of two of said electrodes, and Fig. 5 showing a part of the pot-flange, drawn on an enlarged scale.

Referring to Fig. 1, S denotes a patrix which can be moved vertically by any suitable means (not shown), and the lower end of which is encompassed by a ring K which can be adjusted vertically along the reduced part 8 and secured in its adjusted position also by any suitable mcans (not shown). A simple manner is to provide the patrix-part s with an outer screw-thread and the ring K with an inner screw-thread, as can be imagined without an illustration.

The patrix-part s and the ring K engage a matrix M, the shape of which, especially at its upper part L, is determined by the shape or kind of the pressed part to be locally annealed. In the example shown in Figure 1 the pressed part to be annealed locally is a pot P having a flange p with which it is supported on the correspondingly shaped top-part L of the matrix M.

The'low-tension coil t of the low-tension transformer T is connected. at one end with the patrix S and at the other end with the matrix K. The circuit is completed by the ring K and the pot P. Opposite the flange 79 of the pot the funnel-shaped outer sur- -face of the patrix S is provided Wltll a nonconductive and heat-resisting lining, for instance of asbestos or the like, so that the .part to be annealed, and the disks may current cannot parts 8 and 12.

matrix M and serving for observing the condition of the pot P at the zone where it spark over between the J D are inspection-holes provided in the k the pot is lifted out of the matrix when the annealing procedure is finished. I

It is suitable to the purpose to cover the matrix with a poor heat conductor in order torevent losses by radiation.

upposing, a pot of the kind illustrated that the pot can be inserted into the matrix .in Figure 1 is to be treated, i. e. to be annealed locally, the patrix is raised so much until its flange p rests on the top L thereof.

The next procedure is to shove the pot upon the ring K after this has been so adjusted that it contacts just with that portion of the pot-wall which shall be annealed when the flange 39 touches the matrix-head L. Finally, the primary circuit of the transformer is closedso that the secondary current now circulates through the circuit described, the pot-wall being now heated and annular place where it contacts with the ring K. \Vhen then the desired temperature has been reached, the patrix is lifted out of the matrix and out of the pot, and this latter is lifted separately by the disk U whereafter it is removed from the annealing device and further treated in the manner desired.

The movable members S and U may be moved manually or mechanically, but also in the latter case it is practical to control the respective devices by hand.

There may be several rings K of difierent' axial thickness in order to permit to vary the breadth of the wall-part of the pot to be annealed around its circumference at that annealed, and any ring may be adjusted in height according to the part to be annealed.

Im the modification illustrated in Figure 2, thewall-part to be heated and annealed is subjected to the action of two rotary disks K and Lfl of which one is connected with one end of the coil t, the other with the position of the wallother end-thereof. The breadth of the disks corresponds to the breadth of the pot-wail exchangeable for" smaller or broader ones,

tact with the inner wall of the pot P at three equidistant places, the electric connection being, thus somewhat like the known starconnectionj The electrodes are preferably laminated, as shown especially in Figure 5), so that they accommodate themselves better to the inner wall of the pot. I wish it to be understood, however, that it is immaterial whether the three stationary electrodes are arranged inside or outside the pot, or contact with the inner or the outer surface thereof respectively.

, heating or annealing device is always accom-' The pot is also in this case rotated by pairs of rolls, preferably three pairs, arranged in alternation with the electrodes, and any one ofithethree pairs is connected upto one of the wires of the three-phase system, so that only one third rotation of the pot is required in order to heat'or an neal it around its circumference corresponding to the breadth of the respective rolls.

The pot P shown merely byway of example may have any other shape and it' may consist of iron, steel, brass, aluminium, or another metal; in fact, the pressed part need not be at any rate a pot, but may be another article of manufacture, and the modated to the shape or kind of the respective part or article, as the" case may be.

I claim:

1. A device for the local annealing of pressedparts, comprising relatively spaced movable electrodes having electrical connection with a source of low tension electrical.

energy, and a-contact ringcarried by one of said electrodes adapted to electrically engage a oertain'areaof a part to be annealed, said part also having electrical engagement with a portion of the opposite electrode.

2. A .device for the local annealing of pressed parts, comprising relatively spaced movable electrodes having electrical connection with a source of low tension electrical energy, and a contact ring adjustably carried by and electrically contacting with one of said electrodes adapted to electrically engage a certain area of a part to be annealed, said part being also electrically engaged with the remaining electrode. I

3. A device for the local annealing of pressed parts, comprising'relatively spaced movable electrodes having electrical connection with a source of loW tension electrical energy, and a contactrin'g adjustable along one of said electrodes adapted to be electrically engaged with a certain area of a part being annealed, said part being electrically connected to the opposite electrode in a man-- ner to confine the annealing heat to the aforesaid -area.

4. A device for the local annealing of pressed parts, comprising a patrix having the lower end thereof reduced, a matrix for receiving the reduced end of said patrix tl1erein,-said matrix having that portion of the opening therein receiving thereduc ed end of the patrix formed to receive and support an adjacent portion of a pressed part to be annealed, a contact ring electrically connected to and adjustable over said reduced end of the patrix adapted to electrically contact with a certain area of the pressed part to be annealed,.said patrix and said matrix having connection with a source of low tension electrical energy, and means for moving the pressed parts fromthe matrix subsequently to annealing ofthe same.

In witness whereof I have hereunto set my hand.

EDMUND SCHRODER. 

